Die for making right angles on steel



p 1968 E. E. BRANDNER 3,400,568

DIE FOR MAKING RIGHT ANGLES ON STEEL Filed Oct. 22, 19.65 3 Sheets-Sheet 1 p 1968 E. E. BRANDNER 3,400,568

DIE FOR MAKING RIGHT ANGLES ON STEEL Filed Oct. 22, 1965 3 Sheets-Sheet 2 //Vl E/VTOR.

ER/VEST BRA ND/VER FEE 5.

P 1968 E. E. BRANDNER 3,400,568

DIE FOR MAKING RIGHT ANGLES ON STEEL Filed Oct. 22, 1965 5 Sheets-Sheet 5 1.; 5W1] INVENTOR ERA/E57 BRAND/V5 United States Patent 3,400,568 DIE FOR MAKING RIGHT ANGLES 0N STEEL Ernest E. Brandner, Lyons, lll., assignor of one-half to John F. Cech, North Lake Village, Ill. Filed Oct. 22, 1965, Ser. No. 500,705 6 Claims. (Cl. 72-310) ABSTRACT OF THE DISCLOSURE A die for making right angles including member having a seat, for the operative positioning of any of one of a variety of pairs of die-elements, and mounting a hinged arm having a' greater than 180 degree aircuate-shaped transverse pocket in the under face of the arm for the operative axial insertion of any one of the several cylindrical die-elements each quadrantly-recessed with a metalshaping contour matching that of the one of die-element seated in the base member.

This invention relates to tools of the type used for bending sheet metal.

Heretofore, bending brakes used to form right angled bends in sheet metal, required such force on the male die that the metal was partially sheared at the bend and hence weakened the sheet metal at that point. Also the main part of the sheet metal normally moved off the bed during the bending operation. It was to cure these inher- 61'lt}.d6f6CtS that the present invention was conceived.

The main objects of this invention are: to provide an improved structure of a sheet-metal forming tool; to provide an improved tool of this kind wherein a rocker-arm hinged on a supporting base member mounts a cylindrical'die-element quadrantly-recessed with a metal-shaping contour and relatively supported in a more-than 180 degree arcuate-shaped pocket in the arm and is reciprocably depressible against a die-element on the base member having a metal-shaping contour matching that of the arm-supported die-element; to provide a tool of this kind wherein the die-element in the arm pocket normally is biased to ensure proper registration of the metal-shaping contours of two appropriate matching die-elements; to provide such a normal biasing of the arm-mounted dieelement as will initiate contact of the outermost marginal area of the die-element with the metal positioned on the base-member die-element so as to grip the metal and prevent shifting thereof during the shaping action of the die-element; to provide a tool of this kind whereby multiple units of base-mounted rocker-arms may be arranged in spaced aligned relationship with spanning die-elements to permit shaping lengths of metal greater than can be shaped in an individual unit; and to provide an improved tool of this kind of such simple structure as to make very economical its manufacture and marketing and exceedingly gratifying its use in many kinds of metal shaping.

In the adaptations shown in the accompanying drawmgs:

FIGURE 1 is a perspective view of a single unit sheetmetal forming-tool constructed in accordance with this invention the rocker arm being shown in retracted position;

FIG. 2 is a side elevational view of the same;

FIG. 3 is a plan view of the unit shown in FIGS. 1 and FIG. 4 is a sectional elevation taken on the plane of the line 44 of FIG. 3 showing the rocker arm in its normal fully-retracted position, with a piece of metal in operative position on the base member;

FIG. 5 is a view similar to that of FIG. 4 but showing the rocker arm at the point where the outermost marginal 3,400,568 Patented Sept. 10, 1968 "ice edge of the die-element in the rocker arm is in contact with the strip of metal resting on the lower die-element ready for the shaping of a simple right-angle bend;

FIG. 6 is a view similar to that of FIG. 5 but showing the position of the elements when the forming of the right-angle bend has been completed;

FIG. 7 is a fragmentary perspective of the angle bend as formed in FIG. 6;

FIG. 8 is a perspective view showing a pair of the units of FIG. 1 slightly modified and arranged in spaced relationship and spanned by die-elements for the purpose of shaping longer pieces of sheet-metal than can be readily shaped in a single unit;

FIGS. 9, 11, 13 and 15 show variously contoured dieelements capable of use with a comparable faced base element and rocker arm structure of this kind;

FIGS. 10, 12, 14 and 16 show perspective fragments of sheet metal formed with the respective pairs of dieelements shown in FIGS. 9, 11, 13 and 15;

FIG. 17 is a perspective view of an elongated die-element for use in a pair of rocker-arms on a pair of base elements;

FIG. 18 shows a fiat, rectangularly-recessed piece of sheet-metal to be shaped by the die shown in FIG. 17; and

FIG. 19 shows the form such as shown in FIG. 18, with a flange, along one margin of the recess in the piece of metal.

The essential concept of this invention involves a base member having a seat, for the operative positioning of any of one of a variety of pairs of die-elements, and mounting a hinged arm having a greater than 180 degree arcuateshaped transverse pocket in the under face of the arm for the operative axial insertion of any one of several cylindrical die-elements each quadrantly-recessed with a metal shaping contour matching that of the one of die-element seated in the base member.

A sheet-metal forming-tool embodying the foregoing concept comprises a base member 21 and rocker-arm 22 for the respective positioning thereon of selected pairs of variously-shaped, metal-forming die-elements 23 and 24.

The base member 21, as herein shown, is in the form of a steel block the upper face of which is formed With a recess 26 of substantial depth, length and width. A seat 27 is formed in one end of the recess 26 for operative positioning of one of a pair of die-elements to be described presently. At the end opposite the die-element seat 27 a hinge plate 28 is secured in a seat 29 by a bolt 30. At its forward end plate 28 has a three-quarter cylinder-shaped hub 31 whereon is hinged the rocker arm 22. The base member 21 is provided with suitable apertures 32 for the mounting of the base member 21 on a suitable bed (not shown) to prevent movement of the base when the device is operational.

The rocker arm 22, as herein shown, is of comparatively narrow elongated form, the upper and lower faces tapering rearwardly from a die-element holding-head 33. At its rear end the arm 22 has a more than 180 degree arcuate-shaped socket or seat 34 which rotatively seats on the hub 31. At the point where this arcuate socket 34 terminates the arm 22 is formed with shoulders 36 and 37 disposed at an angle slightly more than degrees. The shoulder 36 serves to contact the plate 28 to limit the upward swinging movement of the arm 22. The shoulder 37 may contact the recessed face 38 of the member 21 to limit the downward, metal-shaping stroke of the arm 22.

The rocker arm 22, on its under face and rearwardly of the head 33, is formed with a more than degree arcuate-shaped die-element retaining-pocket or seat 39.

As here shown the arc of this pocket 39 is approximately degrees more than a semi-circle. The pocket is so located in the arm 22 that its axis 41 is spaced from the hub axis 42 a distance, to all intent and purpose, the same as the juncture of the exterior right-angle face of a stamped metal piece is spaced from the hubaxis 42.

The outer edge of the arm pocket 39 terminates at an under face 46 of the rocker-arm head 33. This arm-end face 46 is disposed in a plane substantially through the axis 42 of the hub 31 and the axis 41 of the pocket 39.

The rocket arm 22 normally is biased into an elevated position, as shown in several of the figures. As here shown such elevation is effected by a compression-coil spring 47 one end of which is seated in a bore 48 on the under face of the rocker arm, directly inward of the pocket 39.

The die-elements 23 and 24 may be structured with various matching metal-shaping contours. Several such possible contours are indicated in FIGS. 6, 9, 11, 13, 15 and 17 for the production of such shapes as those respectively indicated in FIGS. 7 10, 12, 14 and 19.

The die element 23, whatever its metal-shaping contour, is dimensioned for such positioning in the base member seat 27 so that one face 51 thereof is disposed in the plane of the upper face of the base member 21. The other face 52 of the die-element 23 as shown in FIGS. 1-10 and 15-19, is disposed in vertical alignment with a point slightly inward of the axis 41 of the pocket 39when the rocker arm 22 is in its fully-depressed position by an amount substantially equal to the thickness of the sheet metal that is being shaped.

The die-element 24 is cylindrical-shaped. Each such die-element 24 has a quadrant recess or cut-out of the desired metal-shaping contour extending the full axial length of the die-element. Each such cylindrical dieelement 24 is axially insertable into the rocker-arm pocket or seat 39. Thus these die-elements 24 are rotatable in the pocket 39. However, each such die-element 24 is biased by a pair of springs 54, one on each side of the rocker arm, to maintain the die 24 in the position shown in FIG. 2 when the device is at rest. As herein shown these springs 54 are arcuate-shaped tensioned wires or springs which also retain the die-element 24 in proper operative relationship with its companion dieelement 23 and prevent laterally shifting thereof in the seat 39. One end of each spring 54 is secured to one side of the rocker arm 22 by any suitable means such as a screw 55 with the free end of each wire seated in an aperture 56 in the periphery of the respective die-element 24. These springs 54, therefore, tend to predispose the quadrant contour in aligned relationship with its companion die-element 23, and return it to this position when the die is in non-operating position.

The matching metal-shaping contours of these die-elements 23 and 24 are such that on each there is a pair of marginal areas 52-51 on the die elements 23 and a pair of comparable marginal areas 58-58 on the dieelements 24. Such marginal areas need be only extensive enough to ensure a proper gripping of the metal during the metal-shaping operation. For a pair of dieelements 23 and 24, such as shown in FIGS. 6, 9, and 15, these marginal areas constitute a full radius. For a pair of die-elements, such as shown in FIG. 11, these metal-gripping marginal areas constitute only a partial radius inwardly from the die peripheries. In the other figures the radial extent of these marginal areas vary depending upon the contour of the intermediate metalshaping parts thereof. It should be obvious that both dies 23 and 24 must be shaped comparably as illustrated, i. e. must be mated.

The operation of the here-described sheet-metal shaping-tool is as follows:

The desired set of companion or mated die-elements 23 and 24 are properly positioned respectively in the seat 27 of the base member 21 and in the pocket 39 of the rocker arm 22. The strip of metal 40 to be shaped is set in position on the die-element 23, as shown in FIGS. 1-5. Such positioning of the strip of metal 40 should dispose the advancing edge so that it will be within the opening 44 but enough short of the shoulder 45 that when the right angle bend is effected this inner edge will not be disposed at a point beyond contact with the floor of the recess 26 in the base member 21, as shown in FIG. 6.

The rocker arm 22 then is pressured downwardly by any suitable force-manually or by power, to move the die-element 24 into metal-shaping relationship with the die-element 23. As the rocker arm 22 moves toward the metal strip 40 on the base member 21, so as to bring the juncture edge 61 of the marginal area 58 into contact with the strip of metal 40 first and further downward movement will cause the die element to rotate counterclockwise, and continue to move downwardly. From FIGS. 5 and 6, it will be noted that, as the rocker arm 22 continues its downward movement, the juncture edge 61 of the die-element 24 becomes a pivot about which the element 24 rotates counter-clockwise as the other juncture edge 62 depresses the portion 40' of the strip of metal 40, that overhangs the inner edge of the die-element 23, and finally forces it firmly down against the face 52 of that die-element. In such rotation of this dieelement 24, the juncture edges 61 and 62 slide along the respective portions of the strip of metal as the right-angle bend in the strip is completed. The result is a more nearly perfect right-angle bend than is possible to obtain with any other metal-bending tool known to the industry with weakening the metal at the bend. The pressure of this die-element 24 ensures such a retention of the strip of metal against the die-element 23 as will preclude any shifting of the strip of metal as the rocker arm 22 continues its downward movement to the final shape of the strip of metal. As this movement of the rocker arm 22 continues, the die-element 24 will rotate further in the die seat 39 to bring the opposite point 62 of the die-element 24 into contact with the strip of metal and press the portion thereof beyond the edge of the die-element 23 down against the face 52 of that die-element. When the downward force is released, the spring 47 will move the rocker arm to non-operating position and the springs 54 will cause the die 24 to return to position shown in FIG. 2. Thus the bender is ready for another operation automatically.

S0 effective is this equipment in stabilizing the metal in position during the shaping operation that for effecting a right-angle bend the die-elements may have almost any imagined configuration, some of which are indicated in FIGS. 9-15. Moreover, so effective is this tool that a rightangle bend can be made precisely along, or a fraction of an inch away from, one perimeter of a rectangular cutout sheet of metal such as shown in FIG. 19 without distortion.

It is to be understood the juncture point 62 may not always contact the end 40 of the sheet of metal 40. Where a relative short leg of a right angle is required the marginal area 58' may be the one to cause the short end 40' to bend the leg.

It is to be understood that numerous details of this invention may be altered or omitted without departin from the spirit of this invention, as defined by the following claims.

I claim:

1. A sheet-metal shaping-tool comprising, a supporting base member, a die-forming element fixed at one end of the member and having right-angle surfaces defining a predetermined metal-shaping contour inwardly of the apex of the right-angle surfaces, and an arm having an under face hinged at the opposite end of the member with the hinge axis spaced a predetermined distance from the apex of the right-angle surfaces of the one die-element, the arm having formed in the under face thereof a transversely-disposed greater-than degree acruate-shaped pocket for the support of a die-element having a metal-shaping contour matching that of the one die-element, the axis of the pocket being spaced from the hinge axis substantially the same distance as the hinge axis is spaced from the apex of the right-angle surfaces of the One die-element.

2. A sheet-metal shaping-tool as set forth in claim 1 wherein a second die element of cylindrical shape is rotatively positioned in the arm pocket and is quadrantly contoured axially to match the metal-shaping contour of the one die-element.

3. A sheet-metal shaping-tool as set forth in claim 1 wherein the base member is substantially recessed in considerable depth, length and width below, and the one dieelement is separately formed and operatively seated in the recess.

4. A sheet-metal shaping-tool as set forth in claim 3 wherein the quadrantly-shaped contour of the other dieelement forms outer and inner marginal edges for contact with the metal when being shaped between the two die elements, and means on the arm normally biasing the rotative disposition of the second die-element in the arm pocket to initiate contact of the outer marginal edge of the quadrantly-contoured cylindrical die-element with the metal positioned on the one die-element.

5. A sheet-metal shaping-tool comprising, a supporting base member substantially recessed in considerable depth, length and width and defining at one end a die-element seat, a die-element positioned on the base-member seat and having right-angle surfaces defining a predetermined metal-shaping contour inwardly of the apex of the rightangle surfaces, a plate having a three-quarter cylindrical hu-b at one end thereof and fixed on the member at the end of the recess opposite the die-element seat to dispose the hub within the recess, with an arm having an under face and formed with an arcuate-shaped socket at one end dimensioned to embrace the plate hub for hinging the arm for reciprocation on the member with the hinge axis spaced a predetermined distance from the apex of the right-angle surfaces of the one die-element, the arm having formed on the under face thereof a transversely-disposed greater-than-lSO degree arcuate-shaped pocket the axis of which pocket is spaced from the hinge-axis substantially the same distance as the hinge-axis is spaced from the apex of the right-angle surfaces of the one dieelement, a cylindrical die-element quadrantly recessed with a metal-shaping contour having outer and inner marginal edges to match the right angle surfaces of the one die-element, spring means normally biasing the rotative position of the cylindrical die-element to initiate contact of the outermost marginal edge of the quadrant recess of the cylindrical die-element with metal positioned on the dieelement, and other spring means interposed between the member and the arm normally retracting the arm from metal-forming position.

6. A sheet-metal shaping-tool as set forth in claim 5 wherein the arm outwardly of the arcuate socket has flat surfaces angularly disposed for contact respectively with the member and the plate to limit the opposite reciprocal movements of the member relative to its metal-forming position.

References Cited UNITED STATES PATENTS 2,184,949 12/ 1939 Schwartz 72402 2,963,066 12/1960 Nelson 72-319 3,301,034 1/1967 Boettcher 723l9 CHARLES W. LANHAM, Primary Examiner.

G. P. CROSBY, Assistant Examiner. 

